Variable pitch tube propeller



Aug. 5, 1952 A. M. PILZ VARIABLE PITCH TUBE PROPELLER 5 Sheets-Sheet 1 Filed May 19, 1950 INVENTOR. 7Zfrea 77?. P572,

AITU RN EYS g- 5, 1952 A. M. PILZ VARIABLE PITCH TUBE PROPELLER 5 Sheets-Sheet 2 Filed May 19, 1950 mya vzo.

ATTORNEYS Aug. 5, 1952 A, M, vF'ILZ 2,605,606

VARIABLE PITCH TUBE PROPELLER Filed May 19, 1950 3 Sheets-Sheet 5 I 59 as \i 12- 2'? a 1 INVENTOR.

Patented Aug. 5, 1952' Y? UNITED; STAT \VARIAIBIIIE rrron TUBE PROPELLEB. v I, Alfred M. Pilz, Oakland, Calif. I v I 'Application ltlayl9,'1950,SerialNo;163,019

This invention relates to variableipitchpropellers of the type having blades operating in a tube, and in particular this invention includes a tubular housing having propeller blades suspended therein from the outer ends of the blades with .means for changing'the pitch of the blades and with means for mounting the tube whereby the axis thereof is positoned to travel through 360.

The purpose'of this invention is to improve the efficiency of variable pitch propellers mounted in tubular casings by eliminating the hub in the center of the tube and suspending the blades from the outer ends thereof by journalin the outer ends of the blades in the wall of the tube.

' Various attempts have been made to adjust the positions of blades of propellers for varying the pitch thereof but owing to the tremendous loads under which blades of propellers operate it is difficult to mount the blades in a'hub with the pitch of the blades adjustable through the hub.

With this thought in mind'this' invention contemplates a propeller having bladesjournaled by shafts extended from the outer ends of the blades in a surrounding tube with-means on the tube for adjusting the positions of the blades and also with the tube carried by. a turntable whereby the longitudinal axis of the propeller may be swung through an angle of 360.

The object of this invention is, therefore, to provide means for mounting blades of adjustable pitch propellers at the outer ends thereof and means actuating through the outer ends of blades for varying the pitch thereof.

Another object of the invention is to provide a variable pitch propeller having blades mounted in asurrounding tube in which the pitch of the blades may be changed while the propeller is inoperation. v g Another object of theinyention is to provide a propeller of the highest efficiency being capable of moving great quantities of water or air at various speeds.

A further object of the invention is to provide a variable pitch tubular propeller having blades journaled through the outer ends thereof in a surrounding casing and havin means for adjusting the positions of the blades through the surrounding casing, which is of a simple and economical construction.

With these and other objects and advantages in view the invention embodies a rotatable cylindrical housing having a leading end with a beveled surface providing a funnel shaped end.

Other features and advantages of the invention in connection with will appear from the following description taken the drawings wherein:

Figure 1 is a vertical section through the housing and supporting means therefor and showing the bottom of a boat in which the housing isinstalled in section, the section being taken on line I-I ofFigure 3. I 1 1 Figure 2 is a sectional plan through the propeller and housing taken on line 22 of Fi ure 3.

' Figure 3 is a cross section through the-propeller taken on line 3--3 of Figure 2.' 7

Referring now to the drawings wherein'like reference characters denote corresponding parts the improved variable pitch tube propeller of this invention includes a cylindrical rotor l0 journaled in the housing H with a plurality'of blades l2 journaled in the rotor, and'the housing is provided with a turntable l3 that is rotatably mounted in an opening 14 in a surface '15 which may be the bottom of the hull of a ship, and the turntable is provided with a ring gear l6 through which the turntable and rotor are turned'about a center H by a gear l8.

The forward or leading end of the rotor is provided with a thrust flange l9 that is positioned in an annular recess 20 in the housing I l', and the leading end of the housing is provided with a beveled inner surface 2| providing a funnel shaped end, The opposite end of the housing 'I l tapers off with an arcuate surface 22 and the trailing end of the rotor is provided with an outwardly flared, straight or choked flange 23 that extends to the end of the housing. i

The blades l2 are radially positioned in the cylindrical casing or rotor with shafts 24 extended outwardly from discs 25 and the shafts extend through openings'26 in the Wall of the rotor with the discs 25 rotatably mounted in recesses 21. The shafts 24 are provided with arms 28 and pins 29 on the outer ends of the arms 28 extend into an annular groove 30 in the inner surface of an intermediate sleeve 3| that is positioned on the outer surface of the rotor Ill.

The outer surface of the sleeve 3| is provided with spaced longitudinally positioned slots 32 and arms 33 extending from a hub 34 extended into the slots 32 and are slidably mounted therein. The hub 34 is provided with a ring having gear teeth 35 therein that mesh with a pinion 36 on a shaft 31 and the position of the hub 34 and sleeve 3|. may be adjusted by rotating the gear 36.

The sleeve 31 isprovided with angularly positioned slots 38 that are positioned to receive pins 39 extended radially inwardly from the housing 3 .H and, as illustrated in Figure 1 rotation of the sleeve 3| by the gear teeth 35, hub 34 and bars 33 slides the slots 38 over the pins 39 whereby the annular groove 30 travels longitudinally of the rotor, carrying the pins 29 and the arms 28 and thereby rotating the discs 25 upon which the propeller blades l2 are mounted. By this means the positions of the propeller blades are readily adjusted to vary the pitch thereof.

The outer surface of the rotor I8 is provided with spaced recesses 40 in which the arms 28 on the ends of the blade shafts 24 are positioned,

and the outer surface of the rotor is also provided with a ring gear 4| that meshes with a gear 42 on a shaft 43 that may be driven by any suitable power source.

With the parts arranged inthis manner the tube or housing H with the cylindrical rotor Ill and propeller blades carried thereby, journaled therein is suspended through an opening in the bottom or hull of a boat with the tube positioned in the-water below the hull and with thelongitudinal axis of the tube in the same plane as that of the boat. As the rotor I is rotated by-the gear" the blades I2 function as propellerblades drivingthe tube and a craft upon which the'device may be positioned through thewater, and by rotating the gear 3 6 the pitch of the blades'may be increased ordecreased with the speed and driving power required for the boat. The axis of thetube is adjustable from side to side so that the propeller mayalsobe used for steering or for operating the boat in reverse.

it will be understood that the propeller may be provided with any suitable number of blades and the cross section area of the blades may be changed to compensate for different conditions. This propeller eliminates the waste of scattering the created forces sidewise and, therefore,

has a larger power'capacity and greater driving force-aftwardthan theopen type of propel1er..

- The housing II is formed of two complementary sections with the inner surfaces of the sections meeting on the line 45, or as desired.

The column of water at the front or intake,

which the propeller handles, is equal in size to the extreme outside diameter of this propeller unit, and this column of water is-carried through the propeller and controlled evensome distance aftward, after expulsion from this propeller.

' It will be understood thatmodifications may be made in the design and arrangement of the parts without departing fromthe spirit of the invention.

What is claimed is:

1. In a variable-pitch tube propeller, the combination which comprises a cylindrical rotor having radially {disposed openings through the --Wall thereof, propeller blades having shaftsextended from the outer ends journaled in the openings, through the wall of ;the-rotor,a pitohadjusting sleeve slidably and rotatably mounted on the outer surface of the rotor, means on the outer end of the shaft and operatively connected to said sleeve for actuating the blades, said sleeve having an annular groove therein into which the bearing means in connection with the other adjustment means on the ends of the propeller blade shafts extend, said sleeve having angularly disposed slots therein, means for rotating the pitch adjusting sleeve, a cylindrical housing in which the rotor is journaled, pins in the housing extended into the 7 said angularly disposed slots of the sleeve, a driving gear meshing with the pitch adjusting means 'mounted'between the outer surface of the rotor and the inside of the housing, and a rotor driving gear meshing with the pitch adjusting means.

v v 2. In a :variablepitch tube propeller, the combination which comprises a cylindrical rotor havingradially disposed openings through the wall thereof, propeller blades having shafts extended from the outer ends journaled in the opening through-the wall of'the rotor, a pitch adjusting sleeve slidably and rotatably mounted on theouter surface of the rotor, means onthe outer end of the shafts :and operatively connected to said sleeve for actuating the blades, said sleeve having an annular groove therein into which the bearing means in connection-with the other adjustment means :on the ends of the propeller blade-shafts extend,:'said sleeve having angularly disposed slots therein, means for rotating'the pitch adjusting sleeve,.acylindrical housing in .which the rotor is journaled, pins in thehousing extended into the-said angularly disposed slots of the sleeve, a driving gear meshing with the pitch adjusting'means mounted between the outer surface of the rotorand the inside of the housing, a rotor driving gear meshing with the pitch'adjusting means, a turntable extended from one side of the housing, a ring gear on the turntable and an actuating gear meshing with the ring gear of-the turntable foradjusting the direction of the axis of the rotorand housing. 7

3. A variable pitch tube propeller as-ln claim .2 wherein the cylindrical housing has a beveled surface on the leading edge thereof providing a funnel shaped end in which the cylindrical rotor is journaled.

ALFRED M. PILZ.

REFERENCES CITED The following references are of recordin-the file of this patent:

UNITED STATES PATENTS Briggs Sept. 10, 1940 

